DISEASE CHARACTERISTICS:

• Histologically confirmed malignant melanoma

  • Progressive disease that is unresectable or metastatic
• No primary ocular or mucosal melanoma

• At least 1 unidimensionally measurable lesion by physical exam or imaging studies

  • At least 10 mm by caliper for superficial cutaneous disease
  • At least 20 mm by contrast-enhanced or spiral CT scan for visceral or nodal/soft tissue disease
  • No bone metastases as only site of measurable disease

  • Lesions considered non-measurable include the following:

    • Bone lesions
    • Pleural/pericardial effusion
    • Lymphangitis cutis/pulmonis
    • Abdominal masses that are not confirmed and followed by imaging
    • Lesions located in a previously irradiated area
• No brain metastases or leptomeningeal disease
• Considered a medical candidate for dacarbazine treatment

PATIENT CHARACTERISTICS:

Age:

• Any age

Performance status:

• ECOG 0-2

Life expectancy:

• Not specified

Hematopoietic:

• Absolute neutrophil count at least 1,500/mm^3
• Platelet count at least 100,000/mm^3
• Hemoglobin at least 8 g/dL (hematopoietic growth factor or transfusion independent)

Hepatic:

• Bilirubin no greater than 1.5 times upper limit of normal (ULN)
• ALT/AST no greater than 2.5 times ULN
• Alkaline phosphatase no greater than 2.5 times ULN
• Albumin at least 2.5 g/dL
• PT/PTT no greater than 1.5 times ULN
• No history of chronic hepatitis or cirrhosis

Renal:

• Creatinine no greater than 1.5 times ULN OR
• Creatinine clearance at least 50 mL/min

Cardiovascular:

• No uncontrolled congestive heart failure
• No New York Heart Association class III or IV disease
• No symptomatic coronary artery disease (e.g., uncontrolled arrhythmias or recurrent chest pain despite prophylactic medication)
• No cardiovascular signs and symptoms at least grade 2 within the past 4 weeks

Other:

• Intellectually, emotionally, and physically able to maintain an ambulatory infusion pump
• Satisfactory venous access
• No other significant medical disease
• No uncontrolled seizure disorder
• No active infection
• No uncontrolled diabetes mellitus
• No active autoimmune disease
• No other malignancy within the past 5 years except adequately treated basal cell or squamous cell skin cancer or carcinoma in situ of the cervix
• No known hypersensitivity to phosphorothioate-containing oligonucleotides or dacarbazine
• No known HIV infection
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• At least 4 weeks since prior immunotherapy, cytokine, biologic, or vaccine therapy in the adjuvant and/or metastatic setting and recovered
• No concurrent prophylactic growth factors (e.g., filgrastim [G-CSF], sargramostim [GM-CSF] or epoetin alfa) during course 1 of study

Chemotherapy:

• No prior cytotoxic chemotherapy, including regional perfusion

Endocrine therapy:

• No concurrent chronic corticosteroids with an average dose of at least 20 mg of prednisone or equivalent per day

Radiotherapy:

• See Disease Characteristics
• At least 4 weeks since prior radiotherapy and recovered
• No prior radiotherapy to measurable target lesions unless progression occurred at that site or measurable disease developed outside the treated area

Surgery:

• At least 4 weeks since prior surgery and recovered
• No prior organ allografts

Other:

• At least 3 weeks since prior experimental therapy
• No prior intratumoral injection therapy to measurable target lesions unless progression occurred at that site or measurable disease developed outside the treated area
• No concurrent immunosuppressive drugs
• No concurrent anticoagulation therapy except 1 mg/day of warfarin for central line prophylaxis